EQUALIZER HAVING A SUBSTANTIALLY CONSTANT GAIN AT A PRESELECTED FREQUENCY

摘要

An equalizer of a transversal filter type is given a substantially constant gain at a preselected frequency (fp) in a predetermined frequency band of an input and an output signal. For this purpose, the output signal is given by multiplying the routine transversal filter output by a reciprocal of an absolute value of a sum of complex tap gains (Cl to CN+l). Alternatively, the input signal and successively delayed signals (IN and Dl to DN) may be multiplied by the reciprocal before summation. It is possible to approximate the reciprocal by omitting those of the tap gains which are near both ends (as Cl and CN+l). (Fig. 2)